Xerographic toner dispenser



May 10, 1966 P. T. FERRARI ETAL XEROGRAPHIC TONER DISPENSER zSheets-Sheet 1 Filed Dec. 28, 1964 FIG. 3

INVENTOR PATRICK T. FERRARI RUSSELL R. ROBERTS 5} its a. STONE )1 4770EYS May 10, 1966 P. T. FERRARI ETAL XEROGRAPHIC TONER DISPENSER aSheets-Sheet 2 Filed Dec. 28, 1964 1}! O O O O O m o 0 w o O O O O Q 0 OO O 0 O O O O O O OOOOO OOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOO FIG. 4

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INVENTOR SE M m R E R N S H0. T RH H IL $9 J R United States Patent3,250,439 XEROGRAPHIC TONER DISPENSER I Patrick T. Ferrari, Pittsford,Russell R. Roberts, Ontario,

and Joseph B. Stone, Penfieid, N.Y., assignprs to Xerox Corporation,Rochester, N.Y., a corporation of New York Filed Dec. 28, 1%4, Ser. No.421,256 Claims. (Cl. 222225) This invention relates to dispensingapparatus and more specifically, to toner dispensing apparatus for useIn Xerographic machines.

In the process of xerography, development of a latent electrostaticimage is produced by bringing finely-divided powder or toner intocontact with a photoconductive surface. The powder is held on thephotoconductive surface by the electrostatic charge in a patterncorresponding to the latent image. Thereafter, the developed xerographicpowder image may be transferred to a support surface such as paper andfused thereto by the application of heat or solvent vapors. In thedevelopment system of Xerographic machines, the powder supply isdepleted as images are developed and it is necessary, periodically, toadd toner to the development system. Toner, which comprisesfinely-divided pigmented resin, presents unique and unusual problems ofstorage and handling.

One of the methods in common use for developing electrostatic latentimages is described in Walkup Patent 2,681,551 and is known as CascadeDevelopment. In this method, the powder or toner is mixed with agranular carrier material to produce a twocomponent developer which ispoured or cascaded over the photoconductive surface. The function of thecarrier material is to improve the fiow characteristics of the powderand to produce on the powder, by triboelectrification, the properelectrical charge so that the powder will be attracted by theelectrostatic charge in image areas.

The amount of toner in the development system is depleted during thedevelopment process and must be periodically replenished. This toner isadded by means of a toner dispenser. Due to the low melting pointdesirable for proper fusing, the toner is adversely affected by heat,pressure and humidity producing an agglomerating etfect within thedispenser. During the. development process, the carrier assists thetoner in improving the fiow characteristics thereof and preventingclogging. Since the dispenser does not have the help of the granularcarrier material to assist in keeping the toner from agglomerating, itis desirable to have a dispenser which will operate in a positive mannerto insure dispensing of controlled amounts of toner.

In conventional development system-s'the amount of toner present in thedeveloper systems affects the quality of copy produced. If there is anexcess of toner nonimage areas will pick up toner producing undesirablebackground. If there is a deficiency of toner in the system, the imagewill not be fully developed and the copy will be weak and light.

The average amount of toner used per copy can be readily determined. Forexample, in average line copy, printed material covers approximately 5percent of the area of a page. It is therefore possible knowing thenumber of copies made and the amount of toner normally used per copy todetermine the amount of toner to be added after a given number ofcopies. In this manner, equilibrium can be maintained in the system byreplenishing the amount of toner used in the developer. Thus, meteringis practical and useful in either a system where the number of copies iscounted and toner is manually added or an automatic system where thetoner concentration is measured and the toner dispenser actuatedaccordingly.

In development apparatus such asthat dis-closed in copending applicationof Kaupp et al., Serial No. 348,950, filed March 3, 1964, alternatedeveloper pods are used for storing developer material. The type oftoner used in each pod is the same. However, thequant-ity of developerbeads in each pod d-iflers for use in developing line or toner copy. Inthe operation of the developer, one pod is closed cit while the other isin use. It is necessary that the toner dispenser used in such adeveloper housing be capable of dispensing toner to either developerpod.

In automatic xerographic machines of the type disclosed in the abovecited application, Serial No. 348,950, the developer housing includingthe toner dispenser is inverted during development. It is therefore,necessary to have a toner dispenser that is sealed and is not affectedby rotational movement of the developer system.

The primary object of this invention therefore is to improve xerographictoner dispensers for replenishing toner to developer systems.

A further object of this invention is to improve toner dispensers todispense a measuredor metered amount of toner.

A still further object of this invention is to completely enclose tonerdispensers for use in a xerographic developer housing which are invertedduring operation.

Another object of this invention is to improve toner dispensers so thatthe dispensing of toner can be effected by a positive action whichmeters the amount of toner dispensed.

Another object of this invention is to improve toner dispensers topermit toner to be added to either pod of a two pod developer system.

T hose and other objects of this invention are attained by a completelyenclosed toner dispenser in which measured amounts of toner areseparated from the main toner supply and deposited in the developersystem by a positive acting ejector member to either of two locations ina developer housing.

For a better understanding of the invention as well as other objects andfurther features thereof, reference is had to the following detaileddescription of the invention to be read in connection with theaccompanying drawings, wherein:

FIG. 1 is a perspective view partly in section of a xerographic tonerdispenser constructed in accordance mounting taken along lines 3-3 ofFIG. 2;

FIG. 4 is an enlarged front and the dispensing in FIG. 1;

FIG. 5 is a partial top shown in FIG. 1; and,

FIG. 6 is a schematic representation of the developer housing showingthe cascade positions.

For purposes of illustration the toner dispenser constituting thepresent invention is shown in a fiat plate development system of thetype used in Xerographic machines such as that disclosed in the abovecited copending application Serial No. 348,950. In that type ofapparatus, the xerographic plate is clamped in a developer housing suchas the one generally indicated at 10. The Xerographic plate 20 isclamped to the housing by means of a plate clamp 21. The developerhousing is supported on the shaft 12 by a bracket 14 and is rocked aboutthe shaft 12 to the cascade positions shown in dotted lines in FIG. 6.The bracket 14 is attached to a pair of rods 16 which pass through andare secured to the developer housing.

A xerographic plate 20 is held in'the developer hous view of theresilient pad plate of the toner dispenser shown View of the dispensingplate ing 19 by means of a plate clamp 21. A resilient seal 24 extendsaround the opening into which the xerographic plate is fitted to preventspillage of developer material.

The bottom of the developer housing is divided into two pods 26 and 28by means of wall 30. Each pod has a bottom section 32 and 34respectively hinge-d to the wall and secured in place by means of clamps35. The clamps 35 grasp the bottom sections 32 and 34 by means of curvedhooklike appendages 36 and 37 which extend from the bottom sections. Thedeveloper material may be removed from the developer pod bydisconnecting clamp 35 and permitting either bottom section 32 or 34 topivot downward dropping the developer material out of the bottom of thedeveloper pod. A shaft 40 is mounted on top of the dividing wall 30 andsupports a cover fiap 42 which may be pivoted by'means of a lever (notshown). The cover flap 42 alternatively covers either of the developerpods 26 or 28.

One developer pod contains a greater quantity of developer for use indeveloping continuous tone images while the other developer pod containsa lesser quan tity of developer for use in developing line copy. Thecover flap 42 may then be pivoted from the position shown in FIGURE 2when it is desired to develop tone images and is positioned in thedotted line position when it is desired to develop line copy. It is alsopossible to use an electrode plate (not shown) if desired whendeveloping tone images.

A toner dispenser generally designated as is attached 'to the developerhousing by sliding the dispenser along the bracket 51 which is securedto the developer housing. The purpose of the toner dispenser is toreplenish a measured amount of toner to either pod 26 or.28 of thedeveloper housing as is deemed necessary. The toner dispenser is mountedabove the developer pods so that replenishment of the toner is easilyaccomplished. A dispensing plate 53 is slidably mounted on bracket 54-and may be actuated in the direction shown by arrow 55 by means of lever56. The lever 56 is attached to actuating shaft 57. Attached to theactuating shaft 57 are actuating'levers 58 which fit into plate brackets59. A spring 60 which keeps plate 53 securely against bracket 54 ismounted between the actuating shaft 57 and the plate bracket 59. Thetoner particles 52 shown in FIG. 4, are dispensed from the interior ofthe toner dispenser by means of chambers 62 located in dispensing plate53.

To dispense the toner to developer pod 26 positioned on the left handside of the developer housing as shown in FIG. 2, the plate 53 is firstmoved to the right by lever 56 where the chambers 62 will fill withtoner. When the plate is returned to the left resilient polyurethane pad64 will positively force the toner out of the chambers 62 as shown inFIG. 4. To dispense toner to the alternate developer pod 28, the plate53 is first moved to the left where the chambers 62 will fill withtoner. The plate is then returned to the right where it will engage thepolyurethane pads 64. Thus, the dispensing plate 53 can be positioned inany one of 3 positionsone to the left, one to the right, and one in thecenter of the toner dispenser. When the plate 53 is returned the spring60 serves to force the plate 53 against resilient polyurethane pads 64which press down on top of the plate 53. The polyurethane pads. 64 aremounted on the side walls 66 of the toner dispenser. The toner dispenser50 is mounted in the developer housing on developer bracket 51. Thebracket 54 mounted below the toner dispenser is slidably mounted ondeveloper bracket 51. The toner dispenser is stabilized by means of astabilizing bracket 67 which is mounted on the side wall of thedeveloper housing. The developer bracket 51 is rigidly attached to thestabilizing bracket 67.

Toner material may be easily added to the toner dispenser by removingside plate 70 from the developer housing and sliding the toner dispenserbracket 54- along the developer bracket 51 andthereafter removing coveror top wall 72 from the toner dispenser. The amount of toner added toeither of the developer pods 26 or 28 will be equal to the volume of thechambers 62 in plate 53. The number of orifices can be varied todispense a different amount of toner.

It can readily be seen that with a toner dispenser of this type, notoner would be lost from the dispenser during the cascading process,that is, during the pivoting of the developer housing 10 about pivotshaft 12. It is also possible to dispense toner to either the developerpod for use in developing tone images or the developer pod for use indeveloping line copy.

While the invention has been discribed with reference to the structuredisclosed herein, it is not confined to the details set forth, and thisapplication is intended to cover such modifications or changes as maycome within the purposes of the improvements or the scope ofthe-following claims.

What is claimed is:

1. A toner dispenser including:

an enclosed container adapted to hold a quantity of toner material andhaving a bottom wall movable between a first and second position;

means to move said bottom wall between the first and second positions;

a series of openings in the bottom wall of sufiicient size to hold theamount of toner material to be dispensed and positioned in the bottomwall so that they are opento the interior of the container when. thebottom wall is in the first position thereby receiving toner from thecontainer and are open to the outside of the container when the bottomwall is in the second position;

ejecting means adjacent the bottom wall to eject toner material from theseries of openings when the bottom wall is in the second position;

said ejecting means comprising a homogeneous resilient member mountedadjacent to the container in pressing contact with the bottom wall;

the resilient member being flexible to a degree sufiicient to permit themember to deform and extend into the series of openings when in contacttherewith to thereby force toner material out of the opening.

2. A device for dispensing a measured amount of xerographic tonermaterial including:

a housing suitable for holding toner material having top,

end, and side walls;

said side Walls having resilient pads mounted on the bottoms of a plateslidably mounted adjacent the bottom of said housing and having a seriesof chambers therein;

brackets attached to said plate;

an actuating shaft journaled in the end walls of said housing;

actuating levers mounted on said actuating shafts;

said levers communicating with said plate brackets whereby saidactuating shaft will move said plate between a first and a secondposition by means of said levers wherein said chambers will be exposedto the interior of the housing defined by said top, end, and side wallsWhen in said first position;

said chambers thereby filling with'toner and whereby said chambers willengage said resilient pads when in said second position;

said resilient pads thereby ejecting from said chambers a measuredamount of toner equal to the volume of the chambers.

3. A device for dispensing a measured amount of xerographic tonerincluding:

a housing suitable for holding toner material having top, end, and sidewalls;

said side walls having resilient pads mounted thereon;

a plate slidably mounted adjacent the bottom of said housing and havinga series of chambers therein;

means to move said plate between a first and a second position whereinsaid chambers are exposed to the interior of the housing when the plateis in the first position said chambers thereby filling with toner andwhereby upon movement of said plate to the second position said chamberswill engage one of said resilient pads;

said resilient pad in the degree wherein said pad deflects into saidchambers thereby ejecting from said chambers a measured amount of tonermaterial equal to the volume of said chambers.

4. A toner dispenser for dispensing toner material including:

a housing suitable for holding toner material including a slidablebottom wall;

said bottom Wall having chambers therein;

resilient pads mounted juxtapositioned to and engaging said bottom Wall;and

means to move said bottom wall between a first and a second positionwherein said chambers are exposed to the interior of the housing whenthe bottom wall is in the first position filling said chambers therebywith toner and whereby upon movement of said bottom wall to the secondposition and chambers engage at least one of said resilient pads, saidpad resilient in the degree wherein said pad deflects into said orificesthereby ejecting from said chambers a measured amount of toner materialequal to the volume of said chambers.

5. A toner dispenser comprising:

an enclosed container adapted to hold a quantity of toner material andhaving a bottom wall movable t first, second and third positions;

means to move said bottom wall to said first, second and thirdpositions;

two series of openings in the bottom wall of suflicient size to hold theamount of toner material to be dispensed and positioned in the bottomwall so that they are open to the interior of the container when thebottom wall is in the first and third positions thereby receiving tonerfrom the container and are open to the outside of the container when thebottom wall is in the second position, thereby allowing toner ma terialto be dispensed from either series of openings;

ejecting means adjacent the bottom Wall to eject toner material from theseries of openings when the bottom wall is in the first or thirdposition;

said ejecting means comprising two resilient members mounted adjacentthe container in pressing contact with the bottom wall;

the resilient member being flexible to a degree sufiicient to permit themember to deform and extend into the series of openings when in contacttherewith to thereby force toner material out of the opening.

References Cited by the Examiner UNITED STATES PATENTS 6,049' 1/ 1849Dickey 222225 513,940 1/1894 Kelly 222352 2,768,770 10/1956 Morse et al222-276 LOUIS I. DEMBO, Primary Examiner.

HADD S. LANE, Examiner.

1. A TONER DISPENSER INCLUDING: AN ENCLOSED CONTAINER ADAPTED TO HOLD AQUANTITY OF TONER MATERIAL AND HAVING A BOTTOM WALL MOVABLE BETWEEN AFIRST AND SECOND POSITION; MEANS TO MOVE SAID BOTTOM WALL BETWEEN THEFIRST AND SECOND POSITIONS; A SERIES OF OPENINGS IN THE BOTTOM WALL OFSUFFICIENT SIZE TO HOLD THE AMOUNT OF TONER MATERIAL TO BE DISPENSED ANDPOSITIONED IN THE BOTTOM WALL SO THAT THEY ARE OPEN TO THE INTERIOR OFTHE CONTAINER WHEN THE BOTTOM WALL IS IN THE FIRST POSITION THEREBYRECEIVING TONER FROM THE CONTAINER AND ARE OPEN TO THE OUTSIDE OF THECONTAINER WHEN THE BOTTOM WALL IS IN THE SECOND POSITION;